Retinal and peripapillary vessel density increase in recovered COVID-19 children by optical coherence tomography angiography

Characteristics of the radial peripapillary capillary network in patients with COVID-19 based on optical coherence tomography angiography: A literature review

PURPOSE

This review aimed to evaluate the significance of assessing radial peripheral capillary (RPC) network parameters by optical coherence tomography angiography (OCTA) in patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection confirmed by polymerase chain reaction.

METHODS

A literature search was conducted in the PubMed database to select high-quality reviews and original articles on the use of OCTA for visualizing the RPC network and calculating RPC parameters.

RESULTS

The study revealed that systemic hypoxia, hypercoagulable state, and inflammation affect the RPC network in patients with coronavirus disease 2019 (COVID-19). Reduced RPC parameters were observed early in the course of SARS-CoV-2 infection and after several months of follow-up. Additionally, there was a correlation between reduced RPC parameters and subsequent thinning of the retinal nerve fiber layer.

CONCLUSIONS

The OCTA examination of the retina and optic disc should be considered in patients with a history of COVID-19 to assess the impact of systemic hypoxia and inflammation on ocular function. Follow-up assessment of these patients is also necessary to understand the potential consequences of ischemia affecting the optic nerve, retina, and choroid.

Optic nerve head alterations after COVID-19: an optical coherence tomography angiography-based longitudinal study

OBJECTIVE

To evaluate longitudinal changes in peripapillary vessel density (VD) following coronavirus disease 2019 (COVID-19) using optical coherence tomography angiography.

METHODS

As part of a prospective longitudinal observational study, we studied healthy individuals with a history of mild COVID-19 confirmed via real-time polymerase chain reaction. After recovery, we used the Optovue RTVue XR Avanti machine to perform optic nerve head (ONH) imaging. We also assessed the VD of all vessels and of small vessels in the disc and the radial peripapillary capillary (RPC) network at 1 and 3 months post-recovery.

RESULTS

We included 17 patients (34 eyes; mean age: 36.9 ± 10.2 years, range: 24-62 years) who had recovered from COVID-19. No changes were observed in the ONH parameters. However, there was a noticeable trend of increased small vessel VD values in the RPC. These increases were significant for the peripapillary whole, superior hemifield, inferior-temporal, temporal-superior, and superior-temporal small vessels. Moreover, the evaluation of all vessel VD values in the RPC revealed a significant decrease in the inside disc and a significant increase in a grid-based inferior region.

CONCLUSION

COVID-19 may affect VD of the RPC in the ONH, and should be considered in ONH evaluations.

OCT and OCTA evaluation of vascular and morphological structures in the retina in recovered pediatric patients with COVID-19

BACKGROUND

Using OCT and OCTA imaging, we aimed to determine whether COVID-19 induces pathological changes in vascular and morphological structures in the pediatric retina.

METHODS

The current prospective, cross-sectional, observational clinical study included recovered pediatric patients with COVID-19 evaluated between May 2020 and June 2020. Retinal vascular (radial peripapillary, superficial, and deep capillary plexus vessel densities) and morphological (peripapillary retinal nerve fiber, ganglion cell layer, retinal, and choroidal thickness) in the optic disk and macula regions were quantitively assessed using OCT and OCTA. Data were compared between COVID-19 patients and age-matched controls.

RESULTS

The COVID-19 group included 32 eyes of 16 patients and the control group included 32 eyes of 16 cases. Fundus and biomicroscopic examinations revealed no signs of pathology in the COVID-19 group. Mean peripapillary retinal nerve fiber, ganglion cell layer, and choroidal thickness values were significantly greater in the COVID-19 group than in the control group (p<0.05). OCTA indicated that mean superficial and deep capillary plexus vessel densities, and choriocapillaris flow area values were significantly lower in the COVID-19 group than in the control group, whereas mean radial peripapillary capillary plexus vessel density values were significantly higher (p<0.05).

CONCLUSIONS

Even if fundus examination results appear normal in pediatric patients with COVID-19, vascular and morphological changes may be observed in the retina. Further studies with larger numbers of patients are needed to elucidate the clinical significance of vascular and morphological changes in this population.

Retinal findings of COVID-19 patients using Ocular coherence tomography angiography two to three months after infection: Ocular appearance recovered COVID-19 patient

Purpose

The aim of this study was to evaluate the ocular disorders in COVID-19 patients, two to three months after infection.

Methods

In this cross-sectional, historically controlled study, fifty-one COVID-19 patients were compared with thirty-seven age, and gender-matched healthy individuals. After complete ophthalmological examination, all participants underwent peripapillary and macular optical coherence tomography, and optical coherence tomography angiography (OCTA) measurements (OptoVue Inc, Freemont, CA, USA).

Results

The time between the initial onset of symptoms, and ophthalmologic examination was 63.31±15.21 (40–95 days). Ophthalmic examination of all the recovered COVID-19 patients was within normal range. None of the peripapillary and macular OCTA parameters were significantly different between the two groups with pairwise comparisons, but after adjusting for age, gender, axial length, and signal strength index (SSI), recovered COVID-19 eyes showed a significant increase in peripapillary retinal nerve fiber (RNFL) thickness, superficial, and deep macular vessel densities in parafoveal and perifoveal regions compared with healthy control eyes (p<= 0.05). Inner retinal thickness overall is higher in recovered COVID-19 eyes compared to healthy eyes after adjustment.

Conclusion

Patients with moderate-intensity SARS-CoV-2 pneumonia had altered peripapillary and macular vessel density compared to healthy subjects. Further investigation is warranted to analyze the correlation of these changes with disease severity as well as evolution of these changes over time.